Method of making cloth boards and similar articles



July 6-, 1926.

v H. B. SMITH ms'mon OF MAKING CLOTH BOARDS AND SIMILARARTICLES FiledApril 1, 1922 j/ [IVVENOR dr'm Brit/yawn k117i A TTORNEYS Patented July6,1926.

UNITED "STATES HARRY BRIDGHAN SMITH, OF BROOKLYN, NEW YORK, ASSIGNOR TOLIGHTSHIP OF BROOKLYN, NEW YORK, CORPORATION OF CLOTH BOARD CORPORATION,

NEW YORK.

1,5913062 PATENT "OFFICE.

METHOD OF MAKING-CLOTH BOARDS AND SIMILAR ARTICLES.

Application filed April 1,

My invention relates to rapid, simple and economical methods of makingcloth boards or similar articles. I

The general object is to make a cloth board of more or less hollow orcellular construction and of fibrous sheet material, which is verylight, strong and sufficiently stiff, but at the same time to asubstantial degree resilient or flexible, by improved and economlcalmethods, and especially by whatl call a continuous method of production,so that the economy inherent in the article because of the nature ofthematerial and the small amount of material required,'is very much 1increased by the economy in the production operations. a

Briefly described, the invention comprises in one form the advancing ofcontinuous strips or webs of fibrous sheet material, such as paper orsimilar fibrous stock, of suitable qualities and thicknesses, producingupon certain of the webs indentations and projections, or moreparticularly stated, in a particular case ribbing or corrugating such 2web or webs, bringing the .web or webs so treated into contact withother fiatwebs, with adhesive properly applied between the contactingsurfaces, to. form an initial continuous assembly in which thereis acenter or filler of the corrugated or similarly treated material with asubstantially flat facing .sheet on either side of it, longitudinallycreasing or scoring the assembly to form folding lines, and folding overmarginal portions of the assembly along the folding lines, applyingadhesive and pressing down these marginal portions upon the main orcentral part of the assembly with the edges of said margins closelyconfrontin or abutting each other, and then cutting t e assemblytransversely at regular intervals to produce individual cloth boards,the characteristics of which will be sufliciently described hereafter.

The invention also includescertain meth- Ode of treating some or allofthe materials, and by treating is meanta method 'of processing thematerials distinct and different from. corrugating, shaping, bending andcutting them. Such treating in the present invention'consists inapplying to or impregnating some or all of the fibrous sheet materialwith a hardening, stifiening or strengthening agent or material for thepurpose of improving'thestructural qualities 1922. Serial- K015483326.

of the stock in addition to its ordinary qualities, dependent merelyupon the nature of its fibrous composition. -As an example of suchtreatment, one or more sheets of the material is treated with a spitableliquid, such as a solution of sodium silicate, or a suitable glue size,and this may be done by brushing the solution on one or both surfaces ofthe sheet or web, or by passing the web through the solution, or inother ways.

When properly dried, the solid component of the solution remains on orin the fibrous sheet and materially hardens, stifiens or strengthens itand adds to its structural value, so that, for example, a sheet offiller material may be of especially lowgrade or cheap stock and bv thedescribed treatment is strengthened sufli ciently for the purpose inView; or where the stock is of a better grade or quality, the treatmentstill further increases its strength, stiflness or resiliency.

As a variation in the general production method previously described,the materials may be preliminarily partly formed or treated or partlyassembled. For example, one available material is what is called in thetrade single faced corrugated board consisting of a sheet of corrugatedpaper or like material adhesively'secured to a flat facing sheet. Thissingle facedboard may be provided in the form of aroll, and the materialmay be advanced continuously from the roll.

Another facing sheet may beadhesively applied or secured to thecorrugated, or unfaced, surface of the single faced board, the initialassembly being thus completed, and

thereafter the assembly may be treated as before.

.Many other variations may be made with in the principles of theinvention, as .sufiiciently explained in connection with the followingdetail description of the accompanying drawings, which show, in a moreor 1 less diagrammatic way certain representaassembly is entirely com Inone performance of theprocess, suit able sheet material, usually fibrousmaterial, such as paper. cardboard, or the like, is provided in the formof rolls 1, 2 and .3. The materials inthe different rolls may be variedto suit conditions, but in one particular case the sheet material inroll 1 may be of relatively cheap fibrous stock, such as the grade ofstock usually known as straw board, since this, when treated inaccordance with my invention, is especially'cheap and is sufiicientlystrong for many kinds of cloth boards.- The material in the other rolls2 and 3 maybe of higher grade or quality or greater thickness. In oneparticular example this material may be what is commercially known assulphiteboard of moderate thickness, which is sufiiciently stiff andstrong for the purpose in view, and

'at the same time is sufiiciently cheap so that in combination with theother material and treated in accordance with my invention,anexceedingly cheap product is obtained.

" The sheetof material 4 from roll 1 is This step is an example ofvarious ways of treating the core or filler stock to produce in itelevations and depressions, ribs or corrugations, or any otherequivalent formation which provides the necessary structural strengthwhen associated with the other materials. The sheet or web 7 passingaway from the rolls 5 is therefore, in the present f faces of the sheet10 into engagement, and

particular example, a continuous strip 0 corrugated straw board producedfrom the stock in the roll 1.

The cardboard or sulphite board is advanced in the form of a 'strip 8from the roll 2, andpasses over a glue roll 9, by which the undersurface of the sheet is adhesively conditioned. A strip or web 10 ofsimilar material is advanced from the roll3 over a glue roll 11, bywhich the surface of the web which is undermost at that pointissimilarly glued or adhesively conditioned.

' All of the webs are then passed between cooperating pressin rolls 12and 13 with corrugated sheet 7 'etween the flat facing sheets, thisproducing the initial assembly, or initiatin the continuous assembly,consisting of the corrugated sheet in adhesive contact with the fiatfacing sheets. 'The assembly is advanced by any suitable means, forinstance at a point beyond the rolls 12 and 13,-it passes between otherfeed and pressing rolls 14 and 15, all of these rolls.

being suitably drivenin any desired manner. The distance that theassembly travels after initial contact of the parts and before furtheroperations are performed, depends upon the time required for the glue toproperly. set or harden, and to expedite hardening of the glue variousmeans may be employed, for example in the zone 16 between the pairs of.

feed and pressing rolls the assembly may I pass between hot plates orboxes 17 and 18, whichrmay be heated in any suitable way, for instanceby steam circulated through pipes 19 and 20, and by heating in thismanner the glue is rapidly dried or set.

At a point beyond the rolls 14 and 15, the

assembly is treated to facilitate bending along the lines 25, Fig; 2. Inthe. present instance the assembly passes under an abutment roll 26, andbelow this round edge creasing rolls 27. are arranged on a shaft 28, andthe rounded peripheries of these creasing rolls bend and press down theunder facing layer 10 and the irregularities or corrugations of thefiller 7, forming the longitudinal grooves, channels or bending lines25. The upper surfacing layer 8 is substantiallyunaflected by thisoperation.

After the creasing, the creased surface of the assembly is adhesivelyconditioned by passing it over glue roll 30, and adjacent: to this pointthe assembly also passes under a guide plate 32, and at a pointbeyond-the glue roll the guide plate has downwardly and inwardly curvedside portions 34, this guide plate with its side members sufiicientlyrepresenting any suitable assembly bending or forming mechanism. By thismeans, the assembly margins 40 are first bent downward to the positionshown in Fig. 4, and then folded up flat against the inner surface ofthe main or broad flat side then the assembly is passed between pressingrolls 45 and firmly pressed.

The assembly is then cut at regular intervals along transverse lines 50,producing individual cloth boards B, Fig. 5, rotary cutting means beingindicated in the form of rolls '55 provided with cutting blades 56. Itwill be understood, of course, that the particular devices employed'maybe varied greatly.

The completed article B, Fig. 5, is therefore produced from a continuousfiat assembly'consisting of facing sheets and an inter mediatecorrugated sheet- (or its equivalent, as'sufliciently explained above),with marginal portions of the assembly folded over and adhesivelysecured, and with the longitudinal ed es 60 of these margins closelyabutting. Folding is usually performed so that the edges, or at leastthe edge corners 65, are substantially rounded. The assembly is then cutand individual boards B are tile trade for bolt centers or fabricwinders produced, which are very light and-cheap of this class.

In the preceding detail description, the

materials'have been described as being used practically in their naturalstate, that is, the

various sheet fibrous materials are not processed or treated except forthe various gluing, drying, shaping or bending, pressing and cuttingoperations. In some cases, however,.it is desired to additionallyprocess or treat the materials, some or all of them. Fig. 1 shows such atreatment meth-. od applied only to the filler sheet or web 4., at apoint between; its removal from the roll 1 and its corrugation by .rolls5. A suitable hardening, strengthening .or stiffening material, such asin a particular example a solution of sodium silicate, is applied totheweb or sheet after it leaves the roll, and

this solution may entirely impregnate the sheet, or may be more orlessin the nature of a surface coating. After application, it is entirely orsuiiiciently dried before the corrugating operation -or in some casesthe material maybe treated after corrugating.

\Vhen the strengthening material 1s mainly in the nature of a surfacecoating, it may .like articles, comprising advancing a conbe brushed orsprayed on, or otherwise suitably applied. When itis intended toimpregnate the sheet material, however, the sheet may be submerged inthe solution. As an example of the last-named mode of application, Fig.1 shows the web passing down into a tank 70 under a roller 71, so

that the web is immersed in the solution 72" of sodium silicate, andthereafter it is sufficiently dried by passing over a series of rolls 73, one of which, as 74, may be heated by steam or otherwise. Evidently,any of the other webs of material may be similarly treated when desired.

The structural characteristics of the completed article, (Fig. 5), aretherefore in this instance further improved, in addition to the naturalstrength of the fibrous material,

by the. hardening or strengthening agent, this being sufiicientlyindicated in the drawing by the legend applied to the filler material;and it will be understood that this may also apply to the othermaterials when necessary or deslrable. I In some cases this treatmentmay consist' in applying a suitably strong or stifl glue or glue. sizeto an entire surface of a flat sheet which is thereafter brought intoadhesive'contact with the corrugated sheet,

and in this way the adhesive engagement is secured, and at the same timethe glue or size.

covering the entire flat sheet surface or surfaces materially stifi'ensand strengthens it a roll and associated with another surfacing sheet,such for example as the sheet 8, with adhesive properly supplied, andfrom that point on the process may be as previously described. Orcorrugated paper in rolls without any surfacing sheet may be furnishedand advanced and associated with two surfacing sheets, and so on asabove.

In one form of the invention also the method may be understood to beginsubstantially at a point slightly anterior to the creasing rolls 27, orsay at about the point 1 represented by theleft-hand edge of theassembly in Fig. 2; or in other words, in the beginning of the methodthe materials may be already assembled in flat form and glued and theinvention method then consists in creasing, bending, adhesively securingthe margins 40, and cutting off, as above described. R

I claim: 1. A method of producing cloth boards or ,tinuous. assemblyincluding a flat surfacing sheet and a corrugated sheet adhesively con 4nected, creasing the assembly to produce folding lines spaced inwardfrom-the edges,

folding over and adhesively securing the' outer portions of the assemblydefined by the creases upon the flat central portion with I the edges ofsaid outer portions substantially abutting, and severing the assembly 11transverse lines to produce the individual boards.

' 2. A-method of producin cloth boards '1' like articles, comprisingadvancing a continuous assembly including flat surfacing sheets and acorrugated core adhesively connected, creasing the assembly to producefolding lines spaced inward from the edges, folding over the outerportions of the assembly. defined by the creases upon the fiat centralportion with the ed es of said outer portions substantially abutting andsecuring the parts in adhesive contact, and severing the assembly ontransverse lines to produce the individual boards.

3. A method of producing cloth boards or 5 like articles, comprisingadvancing a 'continuous assembly including flat surfacing sheets and anintermediate corrugated sheet witheadhesive between engaging surfaces,applyin heat to set the adhesive, creasing the assem ly to producefolding lines, folding over and adhesively securing outer portions ofthe assembly to the central portion with edges of said outer portionssubstantially abutting and severing the assembly transversely.

4. A method of producing cloth boards or like articles, comprisingadvancing a plurality of continuous flat sheets of fibrous material,corrugating one sheet and bringing-the sheets in flat adhesive contactto produce a continuous assembly, creasing the assembly longitudinally,folding over the outer portions and adhesively securing them to thecentral assembly body with edges {of said outer portions insubstantially abutting relation, and severing the assembly transverselyat regular intervals.

5. A method of producing cloth boards or like articles, comprisinadvancing three continuous flat sheets of filirous material, cor- Irugating the intermediate sheet and bringing the sheets in flat adhesivecontact to produce a continuous assembly, creasing the assembly, foldingover the outer portions and adhesively securing them to the flat centralassembly body with edges of said outer portions in abutting relation,and severing the assembly transversely at regular intervals.

6. A method of making cloth boards and the. like, comprising advancingcontinuous sheets of fiat fibrous material, treating oer tain otthesheet surfaces with adhesive, strengthening, sizing, corrugating anintermediate sheet and connecting it to flat surfacing sheets, creasingthe assembly longitudinally and folding over the outer portions andadhesively securing them to the central

